This invention relates to a connector for electrically connecting connection objects, such as a printed board and a FPC (flexible printed circuit).
As a connector of the type, Japanese Unexamined Patent Application Publication (JP-A) No. H11-339907 discloses a connector for connecting two printed boards faced to each other. The connector comprises an elastic contact having a fixed part fixedly attached to a housing and one and the other split parts branched from one end of the fixed part. The one and the other split parts are disposed in an opening portion of the housing and led out to one and the other surfaces of the housing, respectively.
In the connector, the one and the other split parts as contacting portions of the contact are formed by a single integral component but are independent from each other as spring members. Therefore, it is difficult to achieve a sufficiently high contacting force while suppressing stress so as to prevent occurrence of permanent strain in the one and the other split parts. Further, the housing may possibly be damaged by stress concentration to an area where the fixed part is fixed to the housing. In addition, since the contacting portions of each single contact are shifted in pitch from each other, a narrow pitch can not be achieved so that the connector is increased in size.
As another connector of the type, Japanese Unexamined Patent Application Publication (JP-A) No. 2003-163045 discloses an electrical contact element having a fixed support portion engaged with and held by a holder, a first contact spring part to be brought into press contact with an electronic component, and a second contact spring part to be brought into press contact with a printed board. The first and the second contact spring parts are connected to one end of the fixed support portion and are generally symmetrically folded on upper and lower sides of the fixed support portion. Each of the first and the second contact spring parts has a bent portion formed at an intermediate peak point to serve as a movable contact point, and a free end folded back towards the fixed support portion to form an elastic support portion. However, the above-mentioned structure is not suitable for reduction in profile of the connector.
As still another connector of the type, U.S. Pat. No. 6,328,573 discloses an electrical connector comprising an S-shaped contact formed by press punching and arranged in an opening portion of a housing. The contact has holding portions formed at opposite ends thereof and supported by the housing. In the electrical connector, the contact is bent in an S shape and has contact points formed at opposite sides of an S-shaped portion. The contact points are brought into contact with lands of printed boards faced to each other, respectively. In this manner, the printed boards are electrically connected to each other.
However, since the contact is formed by press punching, the lands of the printed boards may possibly be chipped away by sheared edges of cut surfaces of the contact points when the contact points are brought into contact with the lands. Further, since the contact is merely bent into a generally S shape, the shape of the contact points is not definitely fixed. Consequently, it is difficult to assure stable electrical connection. Following reduction in profile of the connector, an insulator of the connector is reduced in thickness. Therefore, as the number of contacts is increased, opposite ends of the insulator are increasingly warped due to reactive force of the contacts upon assembling the connector to connect the printed boards. Thus, the above-mentioned connector is disadvantageous in assemblability.